Principal Investigator: the researcher accountable for a funded project

Definition

The principal investigator (PI) is the lead researcher responsible for the design, conduct and integrity of a funded project, and the main point of accountability to the funder.

A funder's records track each grant against its PI, covering proposals, reporting obligations and outputs, so responsibility for the work is always clear.

Research Grants
Published on
July 29, 2026
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What is a principal investigator?

The principal investigator (PI) is the lead researcher responsible for the design, conduct and integrity of a funded project. They are the main point of accountability to the funder, the person who answers for how the research is run and how the money is used.

The PI role concentrates responsibility deliberately. While a project may involve many researchers, the PI is the individual the funder holds accountable, which is why research grants are structured around a single named lead rather than a diffuse team.

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What is a principal investigator responsible for?

The PI carries overall responsibility across several dimensions: the scientific direction of the project, the proper use of the awarded funds, meeting reporting and ethics obligations, and the integrity of the work produced. In effect, they are answerable for everything the grant funds.

This breadth is why funders scrutinise the PI as closely as the proposal. In expert evaluation, the track record and standing of the PI often weigh alongside the merit of the research idea itself, because the funder is betting on the person as much as the project.

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Can a project have more than one PI?

A project normally has one principal investigator, though it may have several co-investigators who contribute to the work. Some funders recognise co-PIs, but even then the model is built around clear, named accountability rather than shared or anonymous responsibility.

The reason is practical. When something needs to be answered for, spending, a delayed milestone, a research-integrity question, a funder needs one identifiable person to turn to, not a committee. A single named PI provides that unambiguous point of contact.

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Tracking grants by PI in a platform

A research grant management platform records each grant against its named PI, so proposals, milestone reporting, ethics approvals and research outputs are all tied to a single accountable person, keeping responsibility legible across a portfolio of projects.

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Related terms

The newest terms we've added, the words teams managing grants, sponsorship, and CSR come across most often.

Grant Management

Blind Review

Blind review is the practice of assessing applications with identifying details withheld from reviewers — applicant name, organisation, and often location — so that scores reflect the proposal rather than its author's reputation.

Blind review reduces one kind of bias and cannot remove all of them. Writing quality, named partners and budget scale often reveal the applicant anyway, which is why funders pair it with a declared conflict-of-interest process rather than relying on it alone.

Read the term
Grant Management

Scoring Rubric

A scoring rubric is the document that defines what reviewers assess in an application, the scale they use for each criterion, and how much each criterion counts toward the total score.

The rubric is the instrument; scoring is the act of using it. Publishing it with the call lets applicants address the criteria directly, and keeping it on file lets a funder explain a decision months after it was made.

Read the term
Grant Management

Reviewer Panel

A reviewer panel is the group of evaluators a funder assembles to assess applications, often combining internal staff with external experts to bring the right judgement to each decision.

Giving reviewers a shared scoring grid, managing their workload and consolidating results fairly are what keep evaluation both rigorous and efficient.

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